There are many reasons that Christians choose to attend one church over another: the location, the pastor, the building, the Sunday school or youth group, but across the board one of the most common reasons is the music or worship. Worshiping God in song is an integral part of any church service, but it’s purpose, I think, is often misunderstood.
Why do we sing songs in church, anyway? Let me give you a hint: it’s not just to kill time before the sermon. In fact, Psalm 100 makes the reason for worship very clear.

Psalm 100
1 Make a joyful noise to the LORD, all the earth!
2 Serve the LORD with gladness!
   Come into His presence with singing!
3 Know that the LORD, He is God!
   It is He who made us, and we are His;
   we are His people, and the sheep of His pasture.
4 Enter His gates with thanksgiving,
   and His courts with praise!
   Give thanks to Him; bless His name!
5 For the LORD is good;
   His steadfast love endures forever,
   and His faithfulness to all generations.
Verses 1-3 tell us that once once we fully understand who God is and who we are in relation to Him, we can’t help help but sing!
Know that the LORD, He is God! It is He who made us, and we are His; we are His people, and the sheep of His pasture. (Psalm 100:3)
The LORD is God, He made us to be His own and He cares for us as His highly valued possession. This answers two of the deepest questions that each one of us, at one point or another, must answer: Where do we come from and why are we here? The psalmist assures us that we can know with certainty that the LORD, the eternal creator who reveals himself in scripture, is God. Not only that, but He made us for a purpose and loves us more than we know!
It is based on this key understanding that the psalmist exhorts us to make a joyful noise unto the LORD in verse 1.  
Make a joyful noise to the LORD, all the earth! (Psalm 100:1)
To better understand the true meaning of this verse we need to look closely at the Hebrew word רוּעַ (ruwa), which is translated here as “make a joyful noise”
According to Strong’s concordance, ruwa means to split the ears (with sound), to shout (for alarm or joy): to blow an alarm, to cry aloud, to make a joyful noise, to shout (for joy) in triumph.
In order to get a clearer picture of the meaning of the word ruwa, let’s examine the context in which it is used throughout the Old Testament.    
In so doing we discover:
  • that the Israelites were told to “make a joyful noise” (ruwa) at the the conquest of city of Jericho:
when you hear the sound of the trumpet, then all the people shall shout (ruwa) with a great shout, and the wall of the city will fall down flat. (Joshua 6:5)
  • that the Israelites “made a joyful noise” as the ark of the covenant was brought into their midst:       
And when the ark of the covenant of the LORD came into the camp, all Israel shouted (ruwa) with a great shout, so that the earth rang again. (Samuel 4:5)                       
  • that Ezra and the returning exiles “made a joyful noise” (ruwa) upon the completion of the foundation of the second temple:
And they sang together by course in praising and giving thanks unto the Lord; because he is good, for his mercy endures forever toward Israel. And all the people shouted (ruwa) with a great shout, when they praised the Lord, because the foundation of the house of the Lord was laid. (Ezra 3:11)                           
  • that the prophet Isaiah encouraged us “to shout aloud” (ruwa) as he foresaw and prophesied the redemption of his people:
Sing for joy, you heavens, for the Lord has done this; shout aloud (ruwa), you earth beneath. Burst into song, you mountains, you forests and all your trees, for the Lord has redeemed Jacob, he displays his glory in Israel. (Isaiah 44:23)
  • that the prophet Zechariah encouraged us to “shout for joy” (ruwa) as he described the future coming of the Messiah:
Rejoice greatly, Daughter Zion! Shout (ruwa), Daughter Jerusalem! See, your king comes to you, righteous and victorious, lowly and riding on a donkey, on a colt, the foal of a donkey. (Zechariah 9:9)
  • And finally, that God’s children often “make a joyful noise” (ruwa) when they praise Him for their salvation:
O come, let us sing unto the LORD: let us make a joyful noise (ruwa) to the rock of our salvation. (Psalm 95:1)
Is the idea behind the word ruwa coming into focus? The meaning of the Hebrew word here suggests forcefulness, great joy, shouting in triumph. I am challenged as I read these verses. I don’t know about your church, but this is not how I would describe the worship in my church on most Sunday mornings. Psalm 100 teaches us that we should be so aware of who God is and what he has done for us that we can hardly contain our praise and worship to the LORD. In fact, when we come before him with thanksgiving and praise, we should be so full of joy that we can’t help but ruwa (make a joyful noise)!
When we truly know and understand that God is not only our creator who made us , but also our father who loves us, we should feel compelled to come to Him thanking Him for what he has done and praising Him for who He is.
Ruwa – Make a joyful noise to the LORD, all the earth!
Psalm 100 – Why do we sing in church?